Plugs with two power blades and a ground plug are known in the prior art, as are also the disclosures of my U.S. Pat. No. 5,411,403, "Bridged Electrical Plug", granted May 2, 1995, hereby incorporated by reference herein.
Also known in the art are plugs with two blade contacts and a ground contact each integral with wire-receiving cup-shaped contact portions non-overlappingly facing in different directions, with blade contact portions bent double and formed with a longitudinally retaining set of abutments at a bridge, and plugs with such three cup-shaped contact portions facing in transversely spaced parallel directions but not integral with blade or ground contact portions.